For example, an in-vehicle emergency call apparatus stores positional data obtained from a navigation system, and transmits the stored positional data to a service center as an emergency call when a start trigger occurs, e.g., a traffic accident occurs (refer to Patent document 1).    Patent document 1: JP-2001-043469 A
In the above in-vehicle emergency call apparatus, when the start trigger of the emergency call occurs, an audio communication link is connected with the service center. After the audio communication link is connected, positional data is first transmitted to the service center via the audio communication link. Thereafter the user (driver) can execute a voice call (conversation) with an operator in the service center.
On the other hand, the in-vehicle emergency call apparatus stores positional data items up to a predetermined maximum number (for example, ten items) tracing back to the past from the newest positional data item. When storing a newest positional data item with the positional data items stored up to the predetermined maximum number, the earliest (or oldest) positional data item is eliminated and the newest positional data item is stored. When a start trigger of the emergency call occurs, all of the stored positional data items are transmitted to the service center.
Thus, in the in-vehicle emergency call apparatus which connects the audio communication link with the service center when a start trigger of an emergency call occurs, the following disadvantage may occur. If the positional data items of the predetermined maximum number are stored, it takes a time too long to complete transmitting of all the positional data items because of the low transmission speed of the audio communication link. This does not respond to the user's requirement to quickly notify the service center of the vehicle's positional data.